One in 10 early deaths could be prevented if everyone managed at least half the recommended level of daily physical activity, with just 11 minutes a day (75 minutes a week) of moderate-intensity physical activity – like a brisk walk – enough to reduce your risk of heart disease, stroke and various cancers, say researchers.
Cardiovascular diseases, like heart disease and stroke, are the leading cause of death globally, responsible for 17.9m deaths annually in 2019, while cancers were responsible for 9.6m deaths in 2017. Physical activity, particularly when it is moderate-intensity, is known to reduce the risk of cardiovascular disease and cancer, with the NHS recommending that adults do at least 150 minutes of moderate-intensity activity or 75 minutes of vigorous-intensity activity a week.
To explore the amount of physical activity necessary to have a beneficial impact on several chronic diseases and premature death, researchers from the Medical Research Council (MRC) Epidemiology Unit at the University of Cambridge carried out a systematic review and meta-analysis, pooling and analysing cohort data from all of the published evidence.
This approach allowed them to bring together studies that on their own did not provide sufficient evidence and sometimes disagreed with each other to provide more robust conclusions.
In total, they looked at results reported in 196 peer-reviewed articles, covering more than 30m participants from 94 large study cohorts, to produce the largest analysis to date of the association between physical activity levels and risk of heart disease, cancer and early death.
They found that, outside work-related physical activity, two out of three people reported activity levels below 150 minutes per week of moderate-intensity activity and fewer than one in 10 managed more than 300 minutes a week.
Broadly speaking, they found that beyond 150 minutes weekly of moderate-intensity activity, the additional benefits in terms of reduced risk of disease or early death were marginal. But even half this amount came with significant benefits: accumulating 75 minutes per week of moderate-intensity activity brought with it a 23% lower risk of early death.
Their findings were published in the British Journal of Sports Medicine.
Dr Soren Brage from the MRC Epidemiology Unit said: “If the idea of 150 minutes of moderate-intensity physical activity a week is daunting, then our findings are good news. Doing some physical activity is better than none. This is also a good starting position: if 75 minutes a week is manageable, then step it up gradually to the full recommended amount.”
Seventy-five minutes per week of moderate activity was also enough to reduce the risk of developing cardiovascular disease by 17% and cancer by 7%. For some specific cancers, the reduction in risk was greater – head and neck, myeloid leukaemia, myeloma and gastric cardia cancers were between a 14%-26% lower risk.
For other cancers like lung, liver, endometrial, colon and breast cancer, a 3%-11% lower risk was observed.
Professor James Woodcock from the MRC Epidemiology Unit said: “We know that physical activity, such as walking or cycling, is good for you, especially if you feel it raises your heart rate. But what we’ve found is there are substantial benefits to heart health and reducing your risk of cancer, even if you can only manage 10 minutes every day.”
The researchers calculated that if everyone in the studies had done the equivalent of at least 150 minutes per week of moderate-intensity activity, around one in six (16%) early deaths would be prevented. One in nine (11%) cases of cardiovascular disease and one in 20 (5%) cases of cancer would be prevented.
However, even if everyone managed at least 75 minutes per week of moderate-intensity physical activity, around one in 10 (10%) early deaths would be prevented. One in 20 (5%) cases of cardiovascular disease and nearly one in 30 (3%) cases of cancer would be prevented.
Study details
Non-occupational physical activity and risk of cardiovascular disease, cancer and mortality outcomes: a dose–response meta-analysis of large prospective studies.
Leandro Garcia, Matthew Pearce, Ali Abbas, Alexander Mok, Tessa Strain, Sara Ali, Alessio Crippa, Paddy C Dempsey, Rajna Golubic, Paul Kelly, Yvonne Laird, Eoin McNamara, Samuel Moore, Thiago Herick de Sa, Andrea D Smith, Katrien Wijndaele, James Woodcock, Soren Brage.
Published in the British Journal of Sports Medicine on 28 February 2023
Abstract
Objective
To estimate the dose–response associations between non-occupational physical activity and several chronic disease and mortality outcomes in the general adult population.
Design
Systematic review and cohort-level dose-response meta-analysis.
Eligibility criteria
Prospective cohort studies with (1) general population samples >10 000 adults, (2) ≥3 physical activity categories, and (3) risk measures and CIs for all-cause mortality or incident total cardiovascular disease, coronary heart disease, stroke, heart failure, total cancer and site-specific cancers (head and neck, myeloid leukaemia, myeloma, gastric cardia, lung, liver, endometrium, colon, breast, bladder, rectum, oesophagus, prostate, kidney).
Results
196 articles were included, covering 94 cohorts with >30 million participants. The evidence base was largest for all-cause mortality (50 separate results; 163 415 543 person-years, 811 616 events), and incidence of cardiovascular disease (37 results; 28 884 209 person-years, 74 757 events) and cancer (31 results; 35 500 867 person-years, 185 870 events). In general, higher activity levels were associated with lower risk of all outcomes. Differences in risk were greater between 0 and 8.75 marginal metabolic equivalent of task-hours per week (mMET-hours/week) (equivalent to the recommended 150 min/week of moderate-to-vigorous aerobic physical activity), with smaller marginal differences in risk above this level to 17.5 mMET-hours/week, beyond which additional differences were small and uncertain. Associations were stronger for all-cause (relative risk (RR) at 8.75 mMET-hours/week: 0.69, 95% CI 0.65 to 0.73) and cardiovascular disease (RR at 8.75 mMET-hours/week: 0.71, 95% CI 0.66 to 0.77) mortality than for cancer mortality (RR at 8.75 mMET-hours/week: 0.85, 95% CI 0.81 to 0.89). If all insufficiently active individuals had achieved 8.75 mMET-hours/week, 15.7% (95% CI 13.1 to 18.2) of all premature deaths would have been averted.
Conclusions
Inverse non-linear dose–response associations suggest substantial protection against a range of chronic disease outcomes from small increases in non-occupational physical activity in inactive adults.
See more from MedicalBrief archives:
Short walks could halve premature death risk – Spanish study
WHO: New guidelines on physical activity and sedentary behaviour
Weekend exercise enough to stay fit – decade-long US cohort study
Leisure physical activity linked to health benefits but not work activity